1. Field of the Invention
The present invention is directed to automated recognition of words spoken by users and, more particularly, to recognizing proper nouns using pronunciation specific to one or more geographical areas.
2. Description of the Related Art
A number of techniques are used in automatic recognition of words spoken by users without prior training of the recognition system for each user. One of the most common is limiting the number of words to be recognized, i.e., the grammar used by the recognition system. Another is to attempt to direct the user to a speech recognizer for a particular language, e.g., based on the location of the user. In the case of centralized systems receiving telephone calls from users, the telephone number of the user may provide an indication of the user's pronunciation. In addition, automatic language identification methods, such as those disclosed in U.S. Pat. No. 5,805,771 might be used, or other information provided by a user, such as the language selected for the user interface. However, some words, such as those borrowed from another language or proper nouns, may be pronounced differently than expected for a particular user of some applications, such as voice activated dialing and directory assistance.
Methods of determining pronunciation of personal names have been proposed previously, e.g., in Vitale, Tony, “An Algorithm for High Accuracy Name Pronunciation by Parametric Speech Synthesizer,” Journal of Computational Linguistics, pp. 257-276, 1991 which describes an algorithm to determine ethnic origin of a name based on spelling. However, known methods do not take into account other information that may be available to a system attempting to recognize a name or other proper noun spoken by a user.
Typically, speech recognition systems are localized for a particular language. However, proper nouns may not use the same pronunciation rules as other words in the language, e.g., the string “Jose” in “San Jose,” compared to the same string in “Joseph.” To improve recognition of such proper nouns, it is necessary to augment the speech recognizer of the localized application. There is no known method for accomplishing this automatically or even semi-automatically.